Face mask

ABSTRACT

A face mask has a head band and a visor mounted to the head band. The head band has a support bar for engagement with a brow of a user and a pair of straps connected to the support bar. The straps include a fastener to permit adjustment of the length of the strap to secure the mask to the head of the user. The visor is secured to head band and is detachable to permit replacement.

FIELD OF THE INVENTION

The present invention relates to face masks

DESCRIPTION OF THE PRIOR ART

Face masks are used in a large number of industries to provide protection from a potentially hazardous environment. Some face masks are designed to cover the nose and mouth of the user to inhibit ingestion of hazardous fumes or the expulsion of contagious substances. The masks are relatively simple and therefore can be used on a single occasion and are considered disposable.

Other face masks provide protection for the whole face by having a visor that extends in front of the eyes, nose and mouth. The visors are mounted on a support structure worn by the user which has to accommodate different head sizes and provide proper support for the visor. The support structure can be relatively complex and expensive and therefore do not lend themselves to a single use, disposable device.

The known face masks also tend to be bulky because of the support structure and the orientation of the visor relative to that structure which makes the shipping and storage of the devices relatively costly.

Disposable whole face masks are available that utilise a foam pad attached to the upper edge of the visor to provide a support for the visor on the user's forehead. An elastic band is attached to the visor to hold the facemask in position. This arrangement is relatively complex to manufacture as the foam pad has to be adhered to the visor and the elastic band attached through rivets, which requires 5 separate components to be assembled. Moreover, the spacing of the visor from the user's face is limited by the thickness of the foam, which tends to be compressed by the action of the elastic band. If the visor is damaged or contaminated it is necessary to replace the whole face mask.

US patent application 2011/0265236 shows a face mask with a visor secured to projecting peak of a headband. The headband includes a strap that can be adjusted to provide a snug fit on the user. However, the portion of the headband that engages the user's forehead is relatively rigid by virtue of the peak construction and so cannot accommodate the shape of head of different users

It is therefore an object of the invention to provide a face mask that obviates or mitigates the above disadvantages.

SUMMARY OF THE INVENTION

The present invention provides a face mask having a head band and a visor mounted to the head band. The head band has a flexible support bar for engagement with a brow of a user and a strap assembly is connected to the support bar and extends forwardly and laterally from the support bar. The strap assembly includes a fastener to permit adjustment of the length of the strap to secure the face mask to the head of the user. The visor is secured to head band and is detachable to permit replacement.

Preferably, the visor is spaced from the support bar and as a further preference the strap assembly includes a pair of straps that are secured to the support band in a central zone and project forwardly from the support bar to maintain the visor spaced from the support bar.

BRIEF DESCRIPTION OF THE DRAWINGS

The features of the invention will become more apparent in the following detailed description in which reference is made to the appended drawings wherein:

FIG. 1 is a rear perspective view of a face mask;

FIG. 2 is a side elevation of FIG. 1:

FIG. 3 is a side view similar to FIG. 2 of the face mask in use;

FIG. 4 is a front view of FIG. 3;

FIG. 5 is a top perspective of the face mask in use;

FIG. 6 is a view similar to FIG. 5 of an alternative embodiment;

FIG. 7 is a plan view of the free body configuration of the headband used in the face mask of FIG. 1 and FIG. 6;

FIG. 8. is a view similar to FIG. 1 of a yet further embodiment of face mask;

FIG. 9 is a plan view of the embodiment of FIG. 8;

FIG. 10 is a front elevation of the embodiment of FIG. 8;

FIG. 11 is a rear view of the face mask of FIG. 8; and

FIG. 12 is a section on the line XII-XII of FIG. 9.

FIG. 13 is a perspective view of an alternative form of latch;

FIG. 14 is a side view of the latch of FIG. 13;

FIG. 15 is a perspective view of the latch of FIG. 13 in use;

FIG. 16 is a view similar to FIG. 15 showing the initial stages of releasing the latch;

FIG. 17 is a view similar to FIG. 16 showing the latch released.

FIG. 18 is a perspective view similar to FIG. 8 of a still further embodiment of head band; and

FIG. 19 is a perspective view of a still further embodiment of latch, similar to that of FIG. 8.

DETAILED DESCRIPTION OF THE INVENTION

Referring firstly to FIG. 1, a face mask 10 has a visor 12 and a headband 14. The visor 12 is made from a transparent plastics material, such as PET, A-PET and PET-G, and has a thickness to permit flexing about the major axes. A typical thickness is 1.0 to 3 mm. In its free body state, the visor is a planar sheet and the material characteristics and dimensions permit the sheet to attain a curvature of radius in the order of 70 mm. or less. In a typical embodiment, the visor 12 has major dimensions of 32 cm. wide by 20 cm. high so as to effectively cover a user's face although the dimension will of course vary depending on the intended use and the user.

The upper edge 16 of the visor 12 has a pair of slots 18 at opposite ends that receive tongues 20 formed on the headband 14 as will be described below. The tongues 20 and slots 18 detachably secure the visor 12 to the headband 14 to allow the mask 10 to be assembled and for the visor 12 to be changed as necessary. A pair of central apertures 21 in the upper edge of the visor 12 receive pads 33 on the headband to stabilise the visor vertically.

The head band 14 is molded in one piece from a suitable plastics material such as biocompatible ABS or polypropylene (PP) to be self supporting but exhibit a degree of flexibility. The head band 14 has a support bar 22 that is arcuate but sufficiently flexible to conform generally to the curvature of a user's U brow. The ends 24 of the bar 22 are flared outwardly to avoid direct impingement with the user.

A strap assembly 25 is connected to the support bar 22 and has a pair of straps 26. The pair of straps 26 are connected at spaced locations to a central portion 28 of the support bar 22 and extend forwardly and laterally to overlie the support bar 22 before extending rearwardly to either side of the user's head. The support bar 22 extends to either side of the central portion 28 to provide a pair of resilient fingers 29 that can flex independently to conform the user's brow.

Each of the straps 26 is similar and has a tightly curved end 32 of minimum radius that extends through approximately 180 degrees and connects to the support bar 22. The curved ends 32 cause the straps to extend laterally generally parallel to the support bar 22 and introduce a degree of rigidity to the connection to the support band 22. The curved ends 32 provide a stand off for the respective ones of the straps 26 from the support bar 22 which enables the visor to be positioned forwardly of the face of the user U to enhance comfort.

Pads 33 are molded to the strap 26 adjacent to the curved end 32 to project through holes 21 and support the centre of the visor on the strap. The curved ends 32 merge smoothly with an intermediate portion 34 of the strap 26 that has a progressively increasing radius of curvature away from the support bar 22 and in turn merges with an elongate tail 36. The tails 36 are flexible so as to pass around the head of the user U.

The tongues 20 are molded with the straps 26 adjacent the connection of the intermediate portion 34 and tail 36 and project outwardly from the straps 26. The tongues 20 are formed as rearwardly extending barbs that are undercut toward the strap 26. The tongues are received in the slots 18 and the undercut profile holds the visor against the straps 26.

An outer surface 38 of one of the tails 36 is formed with notches 40 that engage with a resilient latch 42 on the other of the straps 26. The latch 42 has a slot to receive the strap 26 and a pawl connected to the strap by a living hinge to bias the pawl in to engagement with the notches 40. The notches 40 and latch 42 provide a ratchet and pawl releasable fastening that allows the straps 26 to be adjusted so that the headband 14 is a snug fit on the user.

As shown in FIG. 7, the head band is molded as a single piece of compact form with the curved ends 32 and intermediate portions 34 molded with the required curvature and the tails 36 arranged with a 90 degree bend to facilitate the tails 36 passing to the rear of the users head.

In use, the visor 12 is secured to the head band 14 by inserting pads 32 in to holes 21 and pushing the tongues 20 through the slots 18. The visor extends between the curved sections 22 and along respective ones of the straps 26 and the undercut barb on the tongues 20 act in opposite directions to hold the visor 12 on the head band 14. With the visor 12 fitted, the support bar 22 is placed against the brow of the user and the end of one of the straps 26 fed through the latch 42 and adjusted to provide a snug fit.

The fingers 29 of the support bar 22 are independent of the strap assembly 25 and can flex to allow the support bar 22 to conform to the user's brow as the straps are adjusted and distribute the load evenly. The flared ends 24 ensure a comfortable engagement with the user for extended use.

As the straps 26 are adjusted, the visor 12 flexes with the straps 26 to adopt a uniform curvature across the face of the user. The tongues 20 inhibit relative movement between the headband 14 and visor 12 so that as the straps 26 are adjusted, the resilience of the visor maintains a curvature and spacing of the visor from the user U.

As noted above, the curved end 34 of the straps 26 provide a stand off for the visor 12 from the support bar 22 so as to hold the visor away from the face of the user. The spacing of the visor from the support bar 22 vents the upper edge of the face mask 10 and so permits a flow of air across the face of the user to avoid fogging and to effect cooling.

The face mask 10 is formed from the two components, the head band 14 and visor 12 that can be packaged flat unassembled making pack density very efficient and reducing shipping cost. Assembly of the components requires only a simple mechanical connection and the visor 12 may be replaced if damaged or contaminated. The materials used for the components include bio compatible materials for use of the face mask in medical applications. They may also be recyclable, which, together with the efficient packaging, reduce the environmental impact.

A further embodiment is shown in FIG. 6 where an additional support is provided across the top of the head of the user. The additional support is formed as a resilient finger 50 that is secured to the support bar 22 between the curved ends 34 of the straps 26. The finger 50 is curved and flexes to conform to the head of the user. Its orientation provides vertical support for the face mask to avoid undue tightening of the straps 26.

The embodiments described above space the upper edge of the visor 12 from the support bar 22 to permit a flow of air across the face. In certain circumstances it is preferable to inhibit the ingress of air borne contaminants and aerosols between the visor and the support band. The embodiment shown in FIGS. 8 to 12, in which like components will be identified with like reference numerals with a suffix “a” added for clarity, addresses this whilst maintaining the flexibility of the support bar.

Referring to FIGS. 8 to 12, a membrane 60 extends between the support bar 22 a and the intermediate curved ends 34 a on either side of the central portion 28 a. The membrane 60 is integrally molded with the support bar 22 a and straps 26 a so as to form a continuous barrier. The membrane 60 is relatively thin, in the order of 0.3 mm, and is corrugated or pleated across its width, as indicated at 62. The corrugations 62 are arcuate to follow the curvature of the support bar 22 a.

A second membrane 64 extends between the tightly curved ends 32 a and from the central portion 28 a outwardly to the limit of the straps 26 a. The second membrane 64 has a free edge 66 that follows the curvature of the straps 26 a so as to abut the inner face of the visor 12 a adjacent the upper edge 16 a and form an effective seal. The membrane 64 is integrally molded with the central portion 22 a and the straps 26 a and has pleats 68 that fan from the central portion 28 to the free edge 66.

In use, the membranes 60, 64 effectively seal the void between the support bar 22 a and the straps 26 a and visor 12 a. The corrugations 62 and pleats 68 provide a flexibility to the membranes 60, 64 so that flexure of the support band 22 a and the straps 26 a is accommodated without jeopardising the integrity of the seal. The visor 12 a may be attached as described above with the free edge 66 engaging the inner surface to provide a seal and therefore permit visors 12 a to be replaced as necessary. The corrugations 62 and pleats 68 facilitate collection of droplets with the upper edge of the visor providing a dam to inhibit such droplets from falling from the shield on to adjacent surfaces.

The embodiment of FIG. 8 utilises an alternative form of latch 42 a best seen in FIGS. 8 and 9. The latch 42 a is formed as an open loop 70 attached at spaced locations to the strap 26 a. A pair of slots 72 allow passage of the tail 36 a of one of the straps 26 a across the loop 70. The loop 70 and opposed portion of the strap 26 a are formed with projecting lands 74 that define an internal serpentine path between the slots 72. When the tail 36 a is fed through the loop, the notches 40 a engage one of the lands 74 and binds against the other to secure the strap 26 a to provide adjustability for the headband 14 a.

Another form of latch is shown in FIGS. 13 to 17 in which like reference numerals will be used to denote like components with a suffix “b” added for clarity. The latch 42 b has an open loop 70 b consisting of a pair of side walls 80, 82 that extend outwardly from opposite edges of the strap 26 b that are connected by a top wall 84. The top wall extends toward the tail 36 b of strap 26 b but terminates prior to the outer surface to provide slots 72 b.

A pawl 86 extends from the top wall 84 toward the strap 26 b so as to engage the notches 40 b when the tail of the strap 26 b is inserted through the slots 72 b. The notches 40 b are configured with a vertical front wall 88 and a ramped rear wall 90. The pawl 86 is forwardly inclined with a tapered distal end 87 to ride over the ramped rear wall 90 as the strap 26 b is inserted. After insertion, the distal end 87 engages the front wall 88 of the notch 40 b to inhibit reverse movement.

Each of the side walls 80, 82 has an arcuate cut out 92, 94 respectively. The cut out 92 on the side wall 80 extends from the slot 72 b at the trailing edge of the side wall 80 past the pawl 86 and progressively increases in height. Similarly, the cut out 94 extends from the slot 72 at the forward edge of the side wall 82 and past the pawl 86 with progressively increasing height. As seen in FIG. 14, the cut outs 92, 94 overlap to provide a generally ovoid opening 96 which has a width approximately that of the width of the strap 26 b.

In use, the tail 36 b is fed through the trailing slot 72 b and past the pawl 86 as shown in FIG. 15. The ramped rear wall 90 facilitates passage of the strap 26 b past the pawl 86 to emerge through the forward slot 72 b. The strap 26 b can be adjusted to the required length for a secure comfortable fit on the user.

The engagement of the pawl 86 with the front wall 88 and the forwardly inclined attitude of the pawl 86 inhibits removal of the strap 26 b to ensure a stable length for the strap 26 b

To release the strap 26 b from the latch 40 b, the strap 26 b is rotated about an axis perpendicular to its length, as shown in FIG. 16 through about 45 degrees. The bodily movement of the strap 26 b is accommodated by the cut outs 88, 90 to allow the tail 36 b of the strap 26 b to extend diagonally through the latch 40 b.

As the tail 36 b is rotated, the rear wall 90 of notch 40 b bears against the pawl 86 to lift it away from and above the front wall 88 so that the distal end 87 of the pawl 86 is riding on top of the lands between the notches 40 b. In this position, distal end 87 bridges the lands and is held out of the notch 40 b so the tail 36 b may be withdrawn, indicated at FIG. 17. Rotating the tail 36 b as it is withdrawn moves the pawl back in to alignment with the notches 40 b to again inhibit removal. In this way the mask 10 may be incrementally adjusted to provide a custom fit.

A modification of the head band of FIG. 8 is shown in FIG. 18 in which like components will be identified by like reference numerals with a suffix “c” added for clarity. As can be seen in FIG. 18, central portion 28 c of the support bar 22 c has a pair of V-shaped notches 100, 102 formed in the upper and lower edges respectively. The notches 100, 102 terminate on either side of the membrane 64 c to provide a relatively narrow land 104 connecting the left and right portions of the support bar 22 c. The land 104 provides a living hinge integrally molded in to the support bar 22 c to enhance flexibility of the support bar 22 c, promoting improved user comfort. With the living hinge, the support bar 22 c can form more easily to the shape of the user's forehead, by allowing easier increase or decrease of the radius of the support bar 22 c. Furthermore, the two halves of the support bar 22 are now able to flex up and down independently from one another, further reducing the prevalence of pressure points on the forehead of the user. A similar arrangement may be used with the open configuration of face mask shown in FIG. 1.

A further embodiment of the buckle is shown in 19 which is similar to that shown in FIG. 6. Like reference numerals identify like components with a suffix “d” added for clarity. In the embodiment of FIG. 19, the loop 70 d of latch 42 d is formed with a lever arm 106. The lever arm extends beyond the slot 72 d to guide the tail 26 d and provide a mechanical advantage in opening the path between the slots 72 d for insertion and removal of the tail 46 d. In use, when on the head of the user, the opposed lands 74 d are firmly supported by the user's head to hold the latch 42 d closed. When removed from the head, the lands 74 d are able to move apart to facilitate removal of the tail 26 d.

In each embodiment it can be seen that the head band 14 is integrally molded as a single component and is easily connected to the visor 12 by the inter-engagement of projections and holes. The visor and head band provide stability and do not need complex assembly.

Although the invention has been described with reference to certain specific embodiments, various modifications thereof will be apparent to those skilled in the art without departing from the spirit and scope of the invention as outlined in the claims appended hereto. The entire disclosures of all references recited above are incorporated herein by reference. 

We claim:
 1. A head band for supporting a visor, the head band having a support bar for engagement with a brow of a user and a strap assembly spaced forwardly of the support bar and connected to the support bar at a central location, said support bar extending laterally to either side of said central location to provide a pair of fingers that flex independently of said strap assembly.
 2. The head band of claim 1 wherein said strap assembly includes a pair of straps extending in opposite directions from said central location.
 3. The head band of claim 2 wherein said strap assembly includes a latch to permit connection of said straps around a user's head.
 4. The head band of claim 2 wherein the straps are each secured to the support bar in a central zone and project forwardly from the support bar.
 5. The head band of claim 2 wherein attachment points are formed on the straps to secure a visor to the headband.
 6. The headband of claim 5 wherein the attachment points include barbs projecting from the straps.
 7. The headband of claim 4 wherein each of the straps curves progressively outward from the central location.
 8. The headband of claim 7 wherein each of said straps is connected to said support bar through a curved section of minimum radius, said curved section causing said strap to extend laterally generally parallel to and spaced from said support bar.
 9. The headband of claim 8 wherein a membrane extends between the support bar and the straps.
 10. The headband of claim 9 wherein the membrane is pleated.
 11. The headband of claim 8 wherein a membrane extends between curved sections of said straps.
 12. The headband of claim 11 wherein the membrane is pleated.
 13. The headband of claim 1 wherein the support bar is arcuate.
 14. The headband of claim 13 wherein distal ends of said support bar are flared.
 15. The headband of claim 13 wherein said support bar is notched at said central location to provide a hinge and permit relative pivotal movement between opposite ends of said support bar.
 16. The headband of claim 3 wherein the latch includes a ratchet and pawl mechanism.
 17. The headband of claim 16 wherein the pawl is located on one of the straps and engages in notches formed on another of the straps.
 18. The headband of claim 17 wherein the pawl is disengaged from the notch by rotating the one strap relative to the other.
 19. A facemask including a headband having a support bar for engagement with a brow of a user and a strap assembly spaced forwardly of the support bar and connected to the support bar at a central location, said support bar extending laterally to either side of said central location to provide a pair of fingers that flex independently of said strap assembly and a visor secured to the straps.
 20. A facemask according to claim 19 wherein the visor has slots adjacent an upper edge to receive protrusions on the straps and secure the visor to the headband.
 21. A facemask according to claim 19 wherein said strap assembly includes a pair of straps, each connected to said support bar at said central location and extending from said central location in opposite directions, said visor extending between each of said straps.
 22. A facemask according to claim 21 wherein each of said straps is connected to said support bar through a curved section of minimum radius, said curved section causing said strap to extend laterally generally parallel to and spaced from said support bar and said visor extends between said curved sections and along respective ones of said straps. 